Bun 提供了一个快速的 API,用于根据文件系统路径解析路由。此 API 主要面向库作者。目前只支持 Next.js 风格的文件系统路由,但将来可能会添加其他风格。
Next.js 风格
FileSystemRouter 类可以根据 pages 目录解析路由。(Next.js 13 的 app 目录尚未支持。)考虑以下 pages 目录
pages
├── index.tsx
├── settings.tsx
├── blog
│   ├── [slug].tsx
│   └── index.tsx
└── [[...catchall]].tsx
FileSystemRouter 可用于根据此目录解析路由
const router = new Bun.FileSystemRouter({
  style: "nextjs",
  dir: "./pages",
  origin: "https://mydomain.com",
  assetPrefix: "_next/static/"
});
router.match("/");
// =>
{
  filePath: "/path/to/pages/index.tsx",
  kind: "exact",
  name: "/",
  pathname: "/",
  src: "https://mydomain.com/_next/static/pages/index.tsx"
}
查询参数将被解析并返回到 query 属性中。
router.match("/settings?foo=bar");
// =>
{
  filePath: "/Users/colinmcd94/Documents/bun/fun/pages/settings.tsx",
  kind: "dynamic",
  name: "/settings",
  pathname: "/settings?foo=bar",
  src: "https://mydomain.com/_next/static/pages/settings.tsx",
  query: {
    foo: "bar"
  }
}
路由器会自动解析 URL 参数并将其返回到 params 属性中
router.match("/blog/my-cool-post");
// =>
{
  filePath: "/Users/colinmcd94/Documents/bun/fun/pages/blog/[slug].tsx",
  kind: "dynamic",
  name: "/blog/[slug]",
  pathname: "/blog/my-cool-post",
  src: "https://mydomain.com/_next/static/pages/blog/[slug].tsx",
  params: {
    slug: "my-cool-post"
  }
}
.match() 方法还接受 Request 和 Response 对象。url 属性将用于解析路由。
router.match(new Request("https://example.com/blog/my-cool-post"));
路由器将在初始化时读取目录内容。要重新扫描文件,请使用 .reload() 方法。
router.reload();
Reference
interface Bun {
  class FileSystemRouter {
    constructor(params: {
      dir: string;
      style: "nextjs";
      origin?: string;
      assetPrefix?: string;
      fileExtensions?: string[];
    });
    reload(): void;
    match(path: string | Request | Response): {
      filePath: string;
      kind: "exact" | "catch-all" | "optional-catch-all" | "dynamic";
      name: string;
      pathname: string;
      src: string;
      params?: Record<string, string>;
      query?: Record<string, string>;
    } | null
  }
}